A former New South Wales Liberal minister has denied being the mastermind behind “a corrupt scheme to extract donations from prohibited donors” in a day of testimony so spiteful it was nearly brought to an early end.

The former energy minister Chris Hartcher repeatedly tangled with the counsel assisting the Independent Commission Against Corruption (Icac), Geoffrey Watson SC, in Sydney on Monday, maintaining he “did not do any favours for any persons improperly” and had no part in setting up an alleged Liberal party slush fund.

Icac has heard that a former Hartcher employee, Tim Koelma, set up a fake consulting firm before the 2011 election to channel illegal donations to the campaigns of Hartcher and his right-wing allies on the New South Wales central coast. The firm, Eightbyfive, allegedly disguised payments from property developers and other banned donors as invoices for public relations advice.

Spats between Hartcher and Watson slowed proceedings and drew in other barristers, until the commissioner, Megan Latham, threatened to adjourn the hearing. "If anybody wants to question my rulings again, they can face the consequences," she said.

Hartcher at one stage lectured counsel assisting on his style of interrogation. “Why do you keep putting inaccurate and uninformed submissions to the commissioner?” he asked.

Latham told the witness to leave the speeches to his barrister, Alister Henskens SC. Henskens objected: "It is unfair to characterise my submissions as making speeches.”

Earlier, after he was accused of laundering $4,000 through his old law firm’s trust account, Hartcher raged: “I reject that absolutely ... I resent that.”

“Don’t you dare resent anything I say,” Watson replied.

"This is like squabbling children,” Latham muttered at one point.

Hartcher spent the day’s calmer moments batting away evidence and the testimony of other witnesses linking him to the series of alleged fundraising scams under the spotlight at the inquiry.

He was stumped by bank records showing a $2,000 deposit in his account shortly after the same amount had been withdrawn from an account belonging to Koelma’s firm. “There is no reason why I should be receiving any money from Eightbyfive.”

Also a “mystery” was an electronic diary entry made shortly after Hartcher had spoken to executives at Nathan Tinkler’s building company, Buildev, that simply read: “Nathan-Packnac”.

Buildev has been accused of funnelling payments to Eightbyfive through another Tinkler entity, Patinack Farms, a scheme that Hartcher allegedly helped to arrange. “When I saw [the diary entry] there, it puzzled me,” Hartcher said.

When Watson produced a text message sent between Buildev executives saying: “[Hartcher] wants confirmation the invoice has been sent to Patinack Farms”, it required a longer explanation.

“The reason why I introduced Tim Koelma to Buildev was to make it clear to them I was no longer involved in planning … and that they would be better off engaging someone to deal with the opposition on a government relations basis.

“They had to determine how they were going to engage Mr Koelma. I wanted to ensure the engagement had been finalised … so that my involvement could be substantially reduced,” he said.

“I am putting to you that you’re bunging this on,” Watson said. “You’re conveniently hiding behind ‘I don’t recall’ when it suits. And then when you have a speech to make all of a sudden you have a brilliant recall, word for word.”

“I don’t agree with that,” Hartcher said.

By some counts Hartcher told the inquiry he could “not recall” details more than three dozen times over the course of the day.

Watson suggested his memory might be “deficient”.

“Well, I resent that remark,” Hartcher replied.

Numbers scribbled in Hartcher’s handwriting also appeared on a list of political donors, many of them prohibited, prepared by Koelma and another former employee, Ray Carter. “I don’t do ‘7’s’ in that way,” he said at first.

Then: “Yes, look, the 25 is definitely mine and the other two [numbers] are more than likely mine.”

A senior Liberal fundraiser, John Caputo, had earlier told the inquiry that after a 2011 election fundraiser in Sydney he had given up to $6,000 in cheques directly to Hartcher. “I do not recall receiving any cheques from Mr Caputo that night,” Hartcher said on Monday. “I’m not denying it, I just don’t recall it.”

If he had pocketed the cheques that night, Hartcher said he would done so as a “postman”, passing the money on to “the appropriate person”.

Even after Watson’s questions were exhausted, Hartcher continued raising objections. "I am happy to bat on with Mr Watson all day,” he said.